Product details of SDRD SD-306 Wireless Bluetooth Dual Microphone Karaoke Portable 3D Stereo SpeakerProduct DescriptionSupport 3D stereo surround sound, Two wireless microphonesSupport even hello tone one button eliminationPlay micro SD card, 3.5mm input, USB stick or wireless via Bluetooth.Built-in 7.4v / 1800mah lithium battery pack.20W super powerful audio output.Size: 28 x 13 x 11cmSpecification:Feature:Play musicBattery:YesSmart Personal Assistant:NoneChannels:2 (2.0)Cabinet Material:PlasticCommunication:AUX, Bluetooth/ USB DrivePower source:battery, ACOutput power:20WSupport memory card:YesSupport APP:No.Built-in microphone:YesFrequency range:100Hz-18KHzPMPO:20WAudio Crossover:two way